Internal-combustion engine



F. c.- MARTIN INTERNAL COMBUSTION ENGINE July 29 1924. 15035370 me May16. 1'92: 3 ShN'ats-Sfieel 1 July 29 1924.

F. c. MARTIN INTERNAL COMBUSTION ENGINE 3 Sheets-$heet 2 Filed May 15192 July 29, 1924. 1,503,370

- F. c. MARTIN INTERNAL COMBUSTION ENGINE Fil y 16. x92: 3 Shoots-Sheets v g) gwuentoz H F 0. Mgkrizn Patented July 29, 192 1.

FRANK c. MARTIN, or PLATTsMoUT NEBRASKA, ASSIGNOR To MATHEW it MARTIN,

or OMAHA, NEBRASKA.

IN TERN AL-GOMBUfivTION ENGINE.

Application filed May 16, 1921. Serial No. 469,791.

:T all whom it may concern:

Be it known that I, FRANK G. MARTIN, a citizen of the United States,residing at Plattsmouth, in the county of Cass and State of Nebraska,have invented certain new and useful Improvements in anInternal-Combustion Engine; and I do hereby declare the following to bea full, clear, and exact description of the invention, such as willenable others skilled in the art to which it appertains to make and usethe same.

The object of the invention is to prox ide an internal combustion orexplosion engine of the two-cycle valveain-head type wherein thecylinders be built in pairs as in the present approved practice andwherein, while the piston in each cylinder is subjected to the effect ofan exploding charge during each forward movement or cycle,

a complete and eliicient scavenging of the cylinder for the removal ofthe preceding exploded charge may be effected through the introductionof the new charge which is placed under compression before its admissionto the cylinder and which therefore enters the cylinder under conditionsadapting it to expand in a direction impelling the explosive chargetowardflthe exhaust port; to provide an engine of the type indicatedwherein the explosive mixture is inducted into and placed undercompression in 'an auxiliary or compression cylinder from which it isexpelled while under compression into the explosion or power cylinderunder conditions assuring a thorough and uniform distribution andintimate mixture of the ingre' dients,gas and air, to the end that aperfect and complete combustion 1s assured when the explosion occurs;and

combination and'relation of parts of which a preferred embodiment isillustrated in the accompanying drawings, wherem:

Figure'l is a side view partly in section 53 of an engine consisting offour cylinders;

A Figure 8 is a similar view Figure 2 is a plan view of the same,

Figures 3 and 1 are sectional views re spectively on the planesindicated by the lines 3-8 and 4-4: of Figure 1,

Figure 5 is a detail vertical sectional view on the plane indicated bythe line 5-5 of Figure 1, I V

Figure 6 is a detail sectional view of one of the intake valves, f

Figure? is asimilar view of one of the compression or auxiliary cylinderexhaust ports;

v of one of the explosion cylinder inlet ports. I The main or powercylinders 10 are preferably arranged in pairs as indicated in F igure 1with their pistons 11 connected by the 'rod12 to the crank 18 of thecrank shaft let arranged in a suitable casing .15 and carrying the usualfiy wheel 16.

Arranged in supporting coaxial relation with the maln or power cylindersare the auxiliary or compression cylinders 17 preferably of largerdiameter than the main cylinders and having their pistons or plungers 18provided "with cylindrical extensions or drums 19 in which the pistonrods 12 operate andwhich 'are of even: diameter with the pistons of the11mm cylinders, said drums or cylindrical extenslons 19 operatlngthrough packing rings-20 at the lower or inner ends of the vided withthe usual or any preferred pacL- ing rings 2% and the peripheries of thecompression or auxiliary pistons are provided with similar packing rings25. The 11121111 cylinders are provided with exhaust ports 26communicating with a suitable'and preferably common exhaust manifold 27,said exhaust ports being in such a position with relation to thecylinders as to beefficiently exposed when the piston reaches the limitof its downward or inward stroke or cycle as shown in Figure 1.

In the head of each compression or auxiliary cylinder, as indicated inFigure 3 and in detail in Figure 6 there is arranged an intake port 28which is in valved communication with the intake manifold 29, the valve30 being of the inwardly opening type held seated by a spring 31 ofwhich the tension may readily be adjusted by means of a suitable nut 32or the equivalent thereof, the valve being protected by a perforatedguard or cage 33 of conical form serving as a spreader and performingthe additional function of a mixer or baffle for the explosive mixturesupplied by the intake manifold. The cage 33 carries the valve seat 3%and is held in place by a gland nut 35 operating in relation to packingrings 36 and also serving to engage a flange 37 at the inner end of thetubular branch 38 of the intake manifold to insure an efficient andpressure tight joint between the parts, one of the packing rings 36being arranged between the flange 37, and an annular rib 39 on the cage,and another ring being interposed between the rib 39 and the flange &0forming the inner wall of the stufling box which is closed at its outerend as above indicated by the gland nut 35.

During each forward or inward stroke of the compression piston whichaccompanies the corresponding stroke of the main or power piston, acharge of explosive mixture is inducted into the compression cylinderthrough the inlet port 28 by the unseating through suction of the valve30 and hence during the power stroke of the main piston operating underthe effect of the explosion of a charge in the main cylinder, and uponthe return or outward stroke of the compression piston under theinfluence of a power or explosion stroke of the companion cylinder ofthe pair of which it forms a member, the charge of explosive mixturepreviously received is compressed, and in the compressed condition isforced through a reduced outlet port 41 also formed in the head of thecompression cylinder and connected by a pipe or suitable conductor 42with the feed port of the main or power cylinder forming the othermember of the pair of twin or companion cylinders. The liberation of thecharge in the compression cylinder and its introduction through theconductor L2 into the companion power cylinder however does not occuruntil after the same has been compressed by the outward stroke of thecompression piston which occurs during the power stroke of the pis tonin the companion or twin cylinder. For instance, referring to Figure 1wherein the cylinder units a and b are shown in section, the piston ofthe main cylinder of the unit a is shown at the uppermost limit of itsstroke as when about to receive the impulse of an explosive chargeignitable in any suitable way as by means of a sparking plug for whichpurpose a seat 43 is formed in the head of the cylinder, while in theunit I) the pistons are at the innermost limit of their stroke with thecompression cylinder having a charge of the explosive mixture inductedthereinto .during the inward stroke of the compression piston 18. Themain piston 11 of the unit 6 has just reached the limit of its inwardstroke under the influence of the charge exploded in said cylinder andhas just exposed the exhaust port 26 while the piston 18 in thecompanion compression cylinder has compressed its charge and has reachedthe limit of its upward stroke. The exposure of the exhaust port in thepower or main cylinder of the unit I) thus relieves the pressure in saidcylinder to permit of the unseating of the valve 44 which. has held backcharges of compression cylinder of unit a, and thereupon the saidcompressed charge enters and expands suddenly in the upper end of themain cylinder, being spread throughout the area of the end of thecylinder by the bathing action of the valve, and rushes through thecylinder to expel the burnt gases incident to the exploded charge. Uponthe explosion of the charge previously compressed in the'main or powercylinder of the unit a the relative positions of the parts will bereversed, the piston in the compression cylinder of the unit a inductinga fresh charge of the explosive mixture during the stroke of the pistonin the power cylinder of the unit a, the power piston of the unit Z2compressing the charge of explosive mixture which has previously beenintroduced thereto'and the piston in the compression cylinder of unit Z)compressing the charge previously inducted thereinto ready for dischargethrough the conductor 42 into the explosion chamber of the main cylinderof unit a when the piston in the last named cylinder exposes its exhaustport and thus relieves the pressure upon the valve a t controlling thefeed port of that cylinder.

In order to insure the efficiency of the scavenging action of the freshcharge introduced under compression from the compression cylinder of oneunit intd the explosion chamber or cylinder of the other unit, thedischarge end of the conductor 42 is enlarged or expanded as shown at4:5 and the valve 4L4; is located in its closed or seated position flushwith the inner surface of the wall of the cylinder as shown clearly inFigure 8, so that when unseated it serves as a spreader or sprayer whichdischarges the mixture which is introduced under compression in a spreadcondition serving by its release and consequent expansion to afford apositive and effective impelling force to drive the burnt gases andproducts of combustion bodily toward the exhaust port which has beenexposed by the position of the power piston. The valve 4a is providedwith a stem 46 fitted with a seating spring 47 of which the tension maybe adjusted by means of the nut 48 and the seat for the valve is formedin a cage 49 also of conical form as previously described in referenceto the cage 33 with suitable perforations or 53 in the wall of thecylinder and the other of which is interposed between a flange 54 formedon the extremity of the funnel or expanded portion of the conductor 42and the inner end of a gland nut 55.

The end of the conductor 42- which is arranged in communication with theoutlet port 41 from the compression cylinder is flanged as shown at 56and is held in place by a gland nut 57 between which and the flange isinterposed a packing ring 58.

Due to the relative arrangement of the elements of each pair of twin orcomple mental units it will be obvious that the compression strokestaken simultaneously of the main and compression pistons of one unitoccur during the power or explosion impelled stroke of the other unit,the charge being introduced to the compression cylinder of the secondnamed unit during the power stroke of its piston, and when the piston ofthe second named unit reaches the limit of its power or operative strokeand exposes the exhaust port the scavenging charge of fresh gas alreadyin reserve in the compression cylinder of the companion unit isliberated under such conditions as to completely sweep and scavenge theexplosion chamber of said second named unit immediately preparatory tothe power stroke of the piston in the first named unit, so that theintervals between the periods during which the crank shaft is directlyand positively impelled by the power of the explosions are reduced tothe minimum and occur only during the passage of the cranks across thedead center positions when the application of power or pressure theretois useless. The scavenging of each cylinder occurs during the intervalin which the piston is in a practically stationary position at the endof its stroke, and during that interval the previously compressed chargeof fresh gas is introduced into the cylinder in which an explosion hasjust occurred and is permitted to expand and completely fill saidcylinder to the substantially perfect exclusion or expulsion of theburnt or spent ases. c Having thus described the invention, what I claimis: I

An internal combustion engine of the twocycle type having twincooperating units each comprising main and auxiliarycylinders and mainand auxiliary pistons operative respectively in the main and auxiliarycylinders, the pistons in the twin units moving in opposing relation andconnected to a common crank shaft, the auxiliary cylinders being coaxialwith and of greater diameter than the main cylinders to provide anannular ledge engaged by the bases of the main cylinders, an intakemanifold arranged at a one side of the main cylinders and above theauxiliary cylinders and having branches leading-into the auxiliarycylinders through openings in said bases and ledges, the openings insaid ledges each having an annular flange, valve cages positioned insaid openings having annular ribs resting on packing rings carried bythe flanges, flanges on the ends of the branches of the intake manifoldwhich extend into the openings, packing nuts clamping said branches andvalve cages in place and holding the intake manifold to the engineblock, conductors connected with openings in the ledges and havingvalved communication with the outer ends of the main cylinder, saidconductors crossing and leading from the auxiliary cylinder of one unitto the main cylinder of the other unit, and exhaust ports in the sidesof the main cylinders and adapted to be uncovered when the main pistonsdescend a predetermined distance in the cylinders.

In testimony whereof I aflix my signature. 1n presence of two witnesses.

FRANK C. MARTIN.

